In publishing, back-of-the-book indexing may still be a largely manual process. An index, e.g., of a cookbook, may generally be described as a reverse lookup including, e.g., pairs of terms, techniques, or ingredient names mapped to text segments that may contain important usages of those terms, typically specified via page number. Given space constraints within a printed book, it may be beneficial that only the most informative pairings be listed in the index. By contrast, online indexes need not be as concerned with space constraints, and thus a virtually unlimited number of pairing entries may be maintained.